Recently, demands for high resolution and high quality images have been increased in a variety of application fields. However, as images have a higher resolution and higher quality, the amount of information on the corresponding images is further increased. Accordingly, if image information is transmitted using media such as typical wired and wireless broadband lines or image information is stored using typical storage media, information transfer costs and storage costs are increased.
In order to effectively transmit, store, or play information on high resolution and high quality images, a highly-efficient image compression technique may be used.
In order to improve the efficiency of image compression, inter prediction and intra prediction may be used. Pixel values of a current picture are predicted with reference to information on another picture in inter prediction method, and pixel values by using a relationship between pixels in the same picture in intra prediction method.